Liquid dye formulations in non-petroleum based solvent systems

ABSTRACT

A method of coloring a substrate is disclosed that includes the steps of dissolving a vegetable oil ester based solvent wherein the ester is selected from a group consisting of esters having carbon chain length of C-1 to C-18 in a liquid solvent dye to form a low-sulfur containing dye formulation such that the vegetable oil ester is present in an amount of between about 5 and 80 percent by weight of the dye formulation, and mixing sufficient amounts of the dye formulation with the substrate to produce mixtures of predetermined color in which the levels of toxic substrate are substantially less than in otherwise equivalent mixtures that include hydrocarbon-based solvents.

RELATED APPLICATIONS

This is a divisional application of Ser. No. 11/935,162 filed Nov. 5,2007 and now U.S. Pat. No. ______.

BACKGROUND

The present invention relates to liquid dye formulations that includeliquid solvent dyes in non-petroleum based solvent systems such asvegetable oil esters.

Liquid Dye formulations or colorants have widespread commercial uses. Ina liquid context, certain dye formulations are particularly useful, forexample, writing inks (e.g., soft tip markers), printing inks (e.g., inink jet printers) and color coding various petroleum fractions for taxpurposes, octane/cetane levels and to monitor levels of fuel additives.Liquid dyes have become commercially popular due to their hightinctorial strength (i.e., the amount of color per unit colorant) andease of handling at the point of application versus powder dyes.

Liquid solvent dyes generally have a tar like consistency at roomtemperature. Thus, viscosity depressant solvent systems are used todilute these solvent dyes for manufacturing commercially viable dyeformulations.

Those of ordinary skill in the art will know that a dye is a substancethat imparts color when dissolved in a substrate (i.e., the product thatis dyed). Solvent dyes are soluble in a variety of substrates butinsoluble in water. Some of the substrates they are used to color areorganic solvents, hydrocarbon fuels, waxes, lubricants and plastics.Their molecules are typically nonpolar or of minimal polarity, and theydo not undergo ionization. As defined in Hawley's Condensed ChemicalDictionary, Eleventh Edition, Solvent dyes are organosoluble dyes.

Historically, xylene (mixed and single isomers), high flash aromaticsolvents, hydro-treated light naphthenic distillates have been thesolvents of choice for oil soluble applications (e.g., petroleum-basedapplications). For non-petroleum applications, alcohols, straight andbranched chain, glycols, glycol ethers, Mineral Spirits and NMP (i.e.,N-Methyl Pyroldinone) have been the solvents of choice. Theseaforementioned solvent systems present workers and consumers exposureproblems due to their toxicity profile. Similarly, the potentialenvironmental impact has to be monitored as well. Government regulationsare increasingly demanding that manufacturers investigate theirprocesses and formulations to try to find “greener' alternativetechnology. Similarly, it is prudent to reduce the use of products whoseprecursor is crude oil.

Liquid dye formulations have typically used solvents that are amenableto their end use application. An example of this is Solvent Red 164diluted with mineral oil. This is sold as Navipol Red 164 HF as well asother commercial brands. One of its principal uses is the coloration ofautomotive transmission fluid (i.e., substrate) to detect leaks inautomobile transmissions. In this case, mineral oil is the solvent ofchoice due to its likeness to the substrate and its compatibility withautomotive gaskets and seals.

Traditionally, viscosity depressant solvents were chosen based on theirusefulness in the specific end use application and their acceptablesolubility and liquid stability to the dye formulation. Thus, theirtoxicity as well as their impact on the environment was secondary totheir functionality.

Recently, however, there has been greater emphasis on manufacturingenvironment-friendly dye formulations. Environmental programs such asREACH (i.e., Registration, Evaluation, Authorization and Restriction ofChemicals) are being implemented in the European Union. One of themandates of the REACH program is for chemical manufacturers tosystematically replace products containing chemicals that are toxic andharmful to the environment with less toxic products manufactured usingimproved “greener” technology.

As an example of solvent dye use, in the United States, refiners mustadhere to the IRS regulation to mark all off road diesel fuel/heatingoil with 26 PPM of Solvent Red 164 to monitor fuel excise tax evasion.Typically, petroleum-based solvents are used for preparing the dyeformulations for this purpose. When these petroleum-based dyeformulations are used as additives in diesel fuel or heating oil, itincreases the total sulfur content of the fuel. This is becoming aproblem, particularly for refiners in the United States, who must complywith the EPA (Environment Protection Agency) mandate of 15 PPM of sulfuror less.

In view of the aforementioned, a need exists for non-petroleum basedsolvents that are useful in specific end use applications (e.g., haveacceptable solubility and liquid stability to existing commerciallyavailable liquid dyes) but are also environmentally safe and less toxicand do not exceed present or proposed mandates by regulatory agencies.

SUMMARY

In one aspect, the present invention is a dye formulation that usesvegetable oil esters as viscosity depressant solvents.

In another aspect, the present invention is a formulation ofcommercially available liquid solvent dyes in less toxic non-petroleumbased solvent systems.

In yet another aspect, the present invention is a low-sulfur containingdye formulation that meets EPA's mandate of 15 PPM or less of sulfurcontent.

In yet another aspect, the present invention is a method of coloring asubstrate using the dye formulation that includes vegetable oil estersolvent systems.

In yet another aspect, the present invention is a method of using thepresent dye formulation for printing and other writing purposes.

In yet another aspect, the present invention is a method of using thepresent dye formulation for tagging substrates.

The foregoing, as well as other objectives and advantages of the presentinvention and the manner in which the same are accomplished, are furtherspecified within the following detailed description.

DETAILED DESCRIPTION

The invention embraces dye formulations that include non-petroleum basedsolvent systems such as vegetable oil esters.

In one embodiment, the present invention is a low-sulfur containing dyeformulation that includes vegetable oil esters as solvents forcommercially available liquid solvent dyes.

As used herein and as described in Hawley's Condensed ChemicalDictionary, Eleventh Edition, the term vegetable oil refers to oilextracted from the seeds, fruit, or nuts of plants and generallyconsidered to be mixture of mixed glycerides. Vegetable oil esters arederived by esterification of vegetable oils. During the esterificationprocess, the fatty acids of vegetable oils undergo esterificationreaction. This process uses alcohol and gentle heating to convertvegetable oils into vegetable oil esters.

Those skilled in the art will appreciate that vegetable oil esters asused herein can include synthetically or organically derived esters withproperties similar to vegetable oil esters.

The vegetable oil esters used in the present dye formulations replacetraditional solvent systems. For petroleum/oil soluble applications thevegetable oil esters replace solvents such as, but not limited to,xylene (mixed and single isomers), high flash aromatic solvents andhydro-treated light naphthenic distillates. For non-petroleum basedapplications, the vegetable oil esters replace solvents such as, but notlimited to, alcohols (straight and branched chain), limonene, mineralspirits and NMP. As compared to the aforementioned traditional solventsystems, vegetable oil esters are less toxic, biodegradable,environmentally friendly and meet the proposed and existing regulationsin both the United States and the European Union.

Typically, the dye formulations of the present invention includevegetable oil esters that have carbon chain lengths of C-1 to C-18. Moretypically, these vegetable oil esters are methyl or ethyl esters.

Some examples of plants from which vegetable oil esters of the presentinvention are derived include (but are not limited to) corn, cashew nut,oats, lupine, kenaf, calendula, cotton, hemp, soybean, coffee, linseed,hazelnuts, euphorbia, pumpkin seed, coriander, peanut, and the tung oiltree.

Vegetable oil esters are present in the present dye formulation in anamount sufficient to dilute the solvent dye to a liquid consistency.

Further, vegetable oil esters are present in the dye formulation of thepresent invention in an amount sufficient to keep the toxic levels ofthe dye formulation within the currently proposed and existingregulations in the United States (e.g., EPA regulations) as well as inEuropean Union (e.g., REACH regulations).

In order to obtain dye formulations with acceptable viscosity and withacceptable sulfur levels, the amount of vegetable oil esters added inthe dye formulations of the present invention should be between about 5and 80 percent by weight of the dye formulation (e.g., between about 30and 70 percent by weight).

By incorporating vegetable oil esters, the present dye formulations havelow amounts of sulfur that comply with acceptable limits pursuant to theUnited States and European Union regulations. Preferably, the sulfurcontent of the present dye formulation is less than about 15 PPM, and insome embodiments, less than about 10 PPM (e.g., less than about 5 PPM).

For example, Solvent Red 164 diluted with soybean oil methyl ester to anon-volatile content of 30-70 percent will typically have reduction intotal sulfur content to less than about 5 PPM. Whereas, typicalcommercially available products diluted with xylene, aromatic solvents,or mineral oils usually have sulfur content of about 100-250 PPM.

Typically, the dye formulation of the present invention includescommercially available liquid dyes (i.e., liquid solvent dyes) that aredissolved in the aforementioned vegetable oil ester based solvents.

Some examples of liquid solvent dyes that are used in the presentinvention include (but are not limited to), the following dyes and theirblends:

CI Solvent Red 164—4-(phenylazo)-benzamine and mono-tetramethylatedderivatives diazotized and coupled to heptylated 2-Naphthalenol

CI Solvent Red 165—Same as the above—Shaded with Solvent Orange 98

CI Solvent Blue 98—9,10 Anthracenedione, 1,4 Mixed Alkyl-Amino

CI Solvent Blue 79—9,10 Anthracenedone, 1,4 Mixed Alkyl-Alkoxy Amino

CI Solvent Orange 98—1,3 Benzenediol, 2,4 bis (alkylphenyl-azo)

CI Solvent Blue 99—2-methoxy-5-methyl-4-{phenyl-azo}-benzaminediazotized and azo coupled to N-(alkylphenyl)-2 napthalenamine

CI Solvent Red—4-(phenyl-azo)-benzamine and mono-tetramethylatedderivatives diazotized and coupled to N-(2-ethyl-hexyl)-2-napthalenamine

CI SolventRed—2-Napthaleneamine-N-2-(ethyl-hexyl-1-{{2-methylphenylazo}-phenyl}azo}and mixtures thereof

CI Solvent Yellow—3-H-Pyrazol, -3-one, 4-{(4-alkylphenyl)azo}-2,4dihydro-5-methyl-2 phenyl

CI Solvent Black—2 ethylhexyl cupra-amino complex of N-(4alkylphenyl)-1-{{2-methoxy-5-methyl-4-{(phenyl)azo}-2-Naphthalenamine

CI Solvent Yellow—4 alkyl benzamine diazotized and azo coupled to 1:3benzenediol (2:1)

CI Solvent Red 175—Dinaptho 1,2,3,-cd:1,2,3-Im)perylene-9,18-dion,lauryl derivatives

CI SolventBlue—4{(3-trifluoromethyl-phenyl)azo}-2-methoxy-5-benzaminediazotizedand azo coupled to heptylated{N-(4-alkylphenyl)-2-naphthalenamine

CI Solvent Red—Benzamine,N-{2-(butoxy)ethyl}-4-(2-chloro-4-nitrophenyl)azo}-N-ethyl

CI Solvent Red 161

CI Solvent Yellow 143—3H-Pyrazol-3-one,4-{(4-alkylphenyl)azo}-2-(chlorophenyl)-2,4 dihydro-5-methyl-

CI Solvent Yellow 161—Colbate(1), bis{2 {{2-oxo-1-{(phenylaminocarbonyl}-propyl}azo}-phenolate (2-)-hydrogen, C 12-14-tertary alkylamine salt (1:1)

CI Solvent Black 48—Acetylated{Benzamine, N,N-bis {3-alkoxy-2hydroxypropyl}-3-hydroxy-4-{{2-methoxy-5-methyl-4-(phenylazo)-phenyl}azo}--, cobalt complex (2:1)}, N-butyl-1 butanamine salt.

CI Solvent Brown 52—Ferrate (1), bis{5-{N,N-bis(3 alkoxy-2-hydroxypropyl)amino}-2-{(5-chloro-2-hydroxy phenyl)azo}-phenolate(2-)}-hydrogen, N-butyl-1 butanamine (1:1) salt.

CI Solvent Red68—1-[[4-(Phenylazo)phenyl]azo]-2-hydroxy-6,8-naphthalenedisulfonicacid,

CI Solvent Red208—Dibutan-ammonium-bis-[2′,2-dioxy-4-di[2″-hydroxy-3″-alkylpropyl]amino-4′-chloroazobenze]-cobalt(alkyl=n-butyl or n-octyl)

CI Solvent Blue 129—Cuprate(2-),[29H,31H-phthalocyanine-C,C-disulfonato(4-)-.kappa.N29,.kappa.N30,.kappa.-N31,.kappa.N32]-,dihydrogen, compd. with 2-ethyl-N-(2-ethylhexyl)-1-hexanamine (1:2)

CI Solvent Blue—Cuprate(2-),[29H,31H-phthalocyanine-C,C-disulfonato(4-)-.kappa.N29,.kappa.N30,.kappa.-N31,.kappa.N32]-,dihydrogen, compd. with 2-ethyl-N-(2-ethylhexyl)-1-hexanamine (1:2)Benzenemethanol,4-(dimethylamino)-alpha,alpha-bis(4-(dimethylamino)phenyl)-

CI Solvent Black—Benzenemethanol,4-(dimethylamino)-alpha,alpha-bis(4-(dimethylamino)phenyl)-Ferrate(1-),bis[2-[(4-amino-2-hydroxyphenyl)azo]chlorophenolato(2-)]-,N,N,N′N′-tetrakis[mixed 3-butoxy-2-hydroxypropyl and2-hydroxy-3-(octyloxy)propyl] derivs., hydrogen compounds withN-butyl-1-butanamine

CI Solvent Black—1,3-Benzenediamine,4,4′-[(4-methyl-1,3-phenylene)bis(azo)]bis[6-methyl-C.I. Solvent Black 7This substance is identified in the COLOUR INDEX by Colour IndexConstitution Number, C.I. 50415:1

CI Solvent Red—Amines, C12-C14-tert-alkyl,bis[2-[(2-hydroxyphenyl)azo]-3-oxo-N-phenylbutamidato(2-)-cobaltate (1-)(1:1) Spiro(isobenzofuran-1(3H), 9′-(9H)xanthen)-3-One,3′,6′bis(diethylamino)-

CI Solvent Yellow—Phenol,2,6-bis(1-methylpropyl)-4-[(4-nitrophenyl)azo]-

CI Solvent Yellow—Phenol,2,6-bis(1-methylpropyl)-4-[(3-nitrophenyl)azo]-

CI Solvent Yellow—Phenol,2,6-bis(1-methylpropyl)-4-[(3-nitro-4-chlorophenyl)azo]-

CI Solvent Yellow—Phenol,2,6-bis(1-methylpropyl)-4-[(2,4-dinitro-phenyl)azo]-

CI Solvent Yellow—Phenol, 2,6 Disecbutyl-4(3,4 Dichloro Phenyl Azo)-

CI Solvent Yellow—Phenol, 2,6 Disecbutyl-4-(2-Nitro Phenyl Azo)

CI Solvent Yellow—Phenol, 2,6 Disecbutyl-4-(2-chloro-4-Nitro Phenyl Azo

CI Solvent Green—9,10 Anthracenedione, 1,4 (dodecylphenyl)

To assess the commercial viability and the stability of the presentliquid dye formulation, the following experiments were conducted:

Experiment 1

To a two liter three neck round bottom flask equipped for vacuumdistillation, 500 grams of Solvent Red 164 also known as Navipol Red164, a registered trademark of Sunbelt Corporation, was charged. Thecontents were heated and placed under standard laboratory wateraspirator vacuum to remove all the xylene viscosity depressant solvent.The typical maximum temperature used was 110 degrees centigrade. Thexylene was replaced with the methyl ester of soybean oil. The contentswere tested on a UV-Vis Spectrophotometer. The dye formulation wasadjusted with the methyl ester of soybean oil solvent to a tinctorialstrength of 580 AU at 515 nanometers for a 32 PPM solution in isooctane.The dye formulation was stored at ambient, 0 and −20 degrees centigradefor 90 days. The dye formulation was completely stable under allconditions.

Experiment 2

Similarly, various dye formulations according to the present inventionwere formed using the liquid solvent dyes listed hereinabove. These dyeformulations were prepared by replacing traditional viscosity depressantsolvents by methyl ester of soybean oil. The resulting dye formulationswere also stable when subjected to the same storage stability criteriaoutlined in Experiment 1.

Experiment 3

The Navipol Red 164 with the xylene viscosity depressant solvent,utilized in Experiment 1, was tested for total sulfur content. Testingwas performed by Gel Laboratories in Charleston, S.C. using method SW846. The total sulfur content was 170 PPM. The dye formulation inExperiment 1 utilizing the methyl ester of soybean oil (i.e., the dyeformulation as disclosed by the present invention) was also tested. Thetotal sulfur content of this dye formulation with methyl ester assoybean oil was reduced to 3.3 PPM. Several other samples were testedwith similar results.

Experiment 4

26 PPM of the dye formulation prepared in Experiment 1 was added to #2heating oil. The marked heating oil was stored in a similar manner asdetailed in Experiment 1. The dye remained dissolved in the heating oilwith separation noted. Upon standard analytical testing, the heating oilmet all color specifications as required by the U.S. Internal RevenueService regulations.

In another embodiment, the present invention is a method of taggingsubstrates using the dye formulation that includes liquid solvent dyesdissolved in vegetable oil ester solvent systems.

U.S. Pat. Nos. 5,737,871 and 5,156,653 disclose the need for taggingorganic liquids, particularly petroleum fuel. The disclosures of boththese patents are incorporated herein by reference.

Organic liquids, particularly petroleum fuels, are tagged foridentification purposes, such as, tax purposes (e.g., road fuel vs.agriculture fuel), product brand identification, and quality control(e.g., octane identification). In many cases, particularly brandidentification, tagging helps to identify dilution of a tagged fuel withnon-tagged fuel.

The dye solvent of the present invention is tagged by mixing specificquantities of the dye formulation (i.e., a solvent dye dissolved in avegetable oil ester) to a pre-determined amount of substrate to betagged. The amounts of dye formulation and the substrate used for thispurpose is such that the presence of the dye formulation can be easilydetected as and when required for identification of the taggedsubstrate.

For example, the substrates are tagged with about 2-200 PPM of theliquid dye formulation of the present invention.

Typically, the substrates that are tagged by the aforementioned methodinclude (but are not limited to) gasoline, heating oil, kerosene, stoveoil, #2-cycle oil, diesel fuel, paraffin wax, hydrocarbon based markinginks and solvents (e.g., toluene, xylene, isooctane).

For example, Solvent Red 164 is prepared with a vegetable oil ester asits viscosity depressant solvent. 26 PPM of this dye formulation isadded to #2 heating oil to meet the United States Internal RevenueService requirement. The dye formulation is fully miscible and stable inthis substrate and has equivalent properties as compared to dyeutilizing hydrocarbon based viscosity depressants.

In yet another embodiment, the present invention is a method of usingthe dye formulation of the present invention for coloring of varioussubstrates (e.g., coloring of automatic transmission fluid to detectleaks in automobile transmissions and coloring of heating oil todifferentiate between on-road fuels subject to excise taxes and heatingoil and other classes deemed to be tax exempt).

The dye formulation of the present invention generally uses a redsolvent dye diluted with vegetable oil ester based solvent system forthe coloration of transmission fluid (e.g., Solvent Red 164 is dilutedwith soybean oil methyl ester to a standard absorbance value of 580 AUfor a 32 PPM solution in isooctane).

Typically, automatic transmission fluid is a composition based uponselected grades of petroleum hydrocarbon oils incorporating essentialperformance additives. Additives include, for instance, anticorrosionagents, antifoaming agents, viscosity improvers and the aforementioneddye formulation. The latter (i.e., the dye formulation) is added toprovide an immediately visible characteristic to distinguish theautomatic transmission fluid from other oily fluids used in automotivesystems including, for example, lubricating, brake and power steeringfluids. The nature and degree to which the additives are present inautomatic transmission fluid is specified by the automotivemanufacturers.

In yet another embodiment, the present invention is a method of usingthe dye formulation that includes liquid solvent dyes dissolved invegetable oil ester solvents in writing instruments, for ink jetprinting and for coating substrates.

In one embodiment, the present invention is a writing instrument (e.g.,felt tip pens) that uses the less toxic dye formulation of the presentinvention.

In another embodiment, the present invention is an ink jet cartridgefilled with the environmentally friendly dye formulation for printingpurposes.

In yet another embodiment, the present invention is a surface coatedwith the aforementioned dye formulation.

In the specification typical embodiments of the invention have beendisclosed and, although specific terms have been employed, they havebeen used in a generic and descriptive sense only and not for purposesof limitation.

1. A method of coloring a substrate comprising the steps of: dissolving a vegetable oil ester based solvent wherein the ester is selected from a group consisting of esters having carbon chain length of C-1 to C-18 in a liquid solvent dye to form a low-sulfur containing dye formulation such that the vegetable oil ester is present in an amount of between about 5 and 80 percent by weight of the dye formulation; and mixing sufficient amounts of the dye formulation with the substrate to produce mixtures of predetermined color in which the levels of toxic substrate are substantially less than in otherwise equivalent mixtures that include hydrocarbon-based solvents.
 2. A method according to claim 1 wherein the step of mixing sufficient amounts of the dye formulation with the substrate is such that the presence of the dye formulation can be easily detected as and when required for identification of the substrate.
 3. A method according to claim 1 wherein the substrate is selected from a group consisting of transmission fluids, gasoline, heating oil, kerosene, stove oil, #2-cycle oil, diesel fuel, paraffin wax, hydrocarbon based marking inks, wood stain formulations, printing inks, xylene, isooctane and toluene.
 4. A method of coloring a substrate according to claim 1 wherein the step of mixing sufficient amounts of the dye formulation comprises tagging a hydrocarbon automotive fluid with sufficient amounts of the dye formulation.
 5. A method of coloring a substrate according to claim 1 wherein the step of mixing sufficient amounts of the dye formulation comprises mixing sufficient amounts of the dye formulation in a transmission fluid.
 6. A method of coloring a substrate according to claim 1 wherein the step of mixing sufficient amounts of the dye formulation comprises mixing sufficient amounts of the dye formulation for use in writing instruments.
 7. A method of coloring a substrate according to claim 1 wherein the step of mixing sufficient amounts of the dye formulation comprises mixing sufficient amounts of the dye formulation for coating.
 8. A method of coloring a substrate according to claim 1, wherein said liquid solvent dye is selected from the group consisting of CI Solvent Red, CI Solvent Red 2, CI Solvent Red 4, CI Solvent Red 68, CI Solvent Red 161, CI Solvent Red 164, CI Solvent Red 175, CI Solvent Red 208, CI Solvent Red 165, CI Solvent Blue, CI Solvent Blue 4, CI Solvent Blue 79, CI Solvent Blue 98, CI Solvent Blue 99, CI Solvent Blue 129, CI Solvent Orange 98, CI Solvent Yellow, CI Solvent Yellow 3, CI Solvent Yellow 4, CI Solvent Yellow 124, CI Solvent Yellow 143, CI Solvent Yellow 161, CI Solvent Black, CI Solvent Black 2, CI Solvent Black 7, CI Solvent Black 48, CI Solvent Brown 52, CI Solvent Green and their blends.
 9. A method of coloring a substrate according to claim 1, wherein said liquid solvent dye is selected from the group consisting of a CI Solvent Red 164—4-(phenylazo)-benzamine and mono-tetramethylated derivatives diazotized and coupled to heptylated 2-Naphthalenol, a CI Solvent Red 165—4-(phenylazo)-benzamine and mono-tetramethylated derivatives-Shaded with Solvent Orange 98, a CI Solvent Blue 98—9,10-Anthracenedione, 1-4-Mixed Alkyl-Amino, a CI Solvent Blue 79—9,10-Anthracenedione, 1,4-Mixed Alkyl-AlkoxyAmino, a CI Solvent Orange 98—1,3 Benzenediol, 2,4 bis(alkylphenyl-azo), a CI Solvent Blue 99—2-methoxy-5-methyl-4-{phenyl-azo}-benzamine diazotized and azo coupled to N-(alkylphenyl)-2-napththalenamine, a CI Solvent Red—4-(phenyl-azo)-benzamine and mono-tetramethylated derivatives diazotized and coupled to N-(2-ethyl-hexyl)-2-napthalenamine, a CI Solvent Red—2-Napthalenenamine-N-(2-ethylhexyl)-1-{{2-methyl-4-{(2-methylphenyl)azo}-phenyl}azo} and mixtures thereof, a CI Solvent Yellow—3-H-Pyrazol, -3-one, 4-{(4-alkylphenyl)azo}-2,4 dihydro-5-methyl-2 phenyl, a CI Solvent Black—2-ethylhexyl cupra-amino complex of N-(4-alkylphenyl)-1-{{2-methoxy-5-methyl-4-{(phenyl)azo}-2-Naphthalenamine, a CI Solvent Yellow—4-alkyl benzamine diazotized and azo coupled to 1:3 benzenediol (2:1), a CI Solvent Red 175—Dinaptho(1,2,3,-cd:1,2,3,-Im) perylene-9,18-dion, lauryl derivatives, a CI Solvent Blue—4{(3-trifluoromethyl-phenyl)azo}-2-methoxy-5 methylbenzenamine diazotized and azo coupled to heptylated{N-(4 alkyl phenyl)-2-naphthalenamine}, a CI Solvent Red—Benzamine, N-{2-(butoxy)ethyl}-4-(2-chloro-4 nitrophenyl)azo}-N-ethyl, a CI Solvent Red 161, a CI Solvent Yellow 143—3H-Pyrazol-3-one, 4-{(4-alkylphenyl)azo}-2-(chlorophenyl)-2,4 dihydro-5-methyl, a CI Solvent Yellow 161—Colbate (1), bis{2{{2-oxo-1-{(phenylamino carbonyl}-1-propyl}azo}-phenolate (2-)-, hydrogen, C 12-14-tertiary alkyl amine salt (1:1), a CI Solvent Black 48—Acetylated{Benzamine, N,N-bis{3-alkoxy-2 hydroxypropyl}-3-hydroxy-4-{{2-methoxy-5-methyl-4-(phenylazo)-phenyl}azo}- -, cobalt complex (2:1)}, N-butyl-1 butanamine salt, a CI Solvent Brown 52—Ferrate (1), bis{5-{N,N-bis(3 alkoxy-2-hydroxy propyl)amino}-2-{(5-chloro-2-hydroxy phenyl)azo}-phenolate (2-)}-hydrogen, N-butyl-1 butanamine (1:1) salt, a CI Solvent Red 68—1-[[4-(Phenylazo)phenyl]azo]-2-hydroxy-6,8-naphthalenedisulfonic acid, a CI Solvent Red 208—Dibutan-ammonium-bis-[2′,2-dioxy-4-di[2″-hydroxy-3″-alkylpropyl]amino-4′-chloroazobenze]-cobalt (alkyl=n-butyl or n-octyl), a CI Solvent Blue 129—Cuprate(2-), [29H,31H-phthalocyanine-C,C-disulfonato(4-)-.kappa.N29,.kappa.N30,.kappa.-N31,.kappa.N32]-, dihydrogen, compd. with 2-ethyl-N-(2-ethylhexyl)-1-hexanamine (1:2), a CI Solvent Blue—Cuprate2-), [29H,31H-phthalocyanine-C,C-disulfonato(4-)-.kappa.N29,.kappa.N30,.kappa.-N31,.kappa.N32]-, dihydrogen, compd. with 2-ethyl-N-(2-ethylhexyl)-1-hexanamine (1:2) Benzenemethanol, 4-(dimethylamino)-alpha,alpha-bis(4-(dimethylamino)phenyl), a CI Solvent Black—Benzenemethanol, 4-(dimethylamino)-alpha,alpha-bis(4-(dimethylamino)phenyl)-Ferrate(1-), bis[2[(4-amino-2-hydroxyphenyl)azo]chlorophenolato(2-)]-, N,N,N′N′-tetrakis[mixed 3-butoxy-2-hydorxypropyl and 2-hydroxy-3-(octyloxy)propyl] derivs., hydrogen compounds with N-butyl-1-butanamine, a CI Solvent Black—1,3-Benzenediamine, 4,4′-[(4-methyl-1,3-phenylene)bis(azo)]bis[6-methyl-C.I. Solvent Black 7 a CI Solvent Red—Amines, C12-C14-tert-alkyl, bis[2-[(2-hydroxyphenyl)azo]-3-oxo-N-phenylbutamidato(2-)-cobaltate (1-) (1:1) Spiro(isobenzofuran-1(3H), 9′-(9H)xanthen)-3-One, 3′,6′bis(diethylamino), a CI Solvent Yellow—Phenol, 2,6-bis(1-methylpropyl)-4-[(4-nitrophenyl)azo], a CI Solvent Yellow—Phenol, 2,6-bis(1-methylpropyl)-4-[(3-nitrophenyl)azo], a CI Solvent Yellow—Phenol, 2,6-bis(1-methylpropyl)-4-[(3-nitro-4-chlorophenyl)azo], a CI Solvent Yellow—Phenol, 2,6-bis(1-methylpropyl)-4-[(2,4-dinitro-phenyl)azo], a CI Solvent Yellow—Phenol, 2,6 Disecbutyl-4(3,4 Dichloro Phenyl Azo), a CI Solvent Yellow—Phenol, 2,6 Disecbutyl-4-(2-Nitro Phenyl Azo), a CI Solvent Yellow—Phenol, 2,6 Disecbutyl-4-(2-chloro-4-Nitro Phenyl Azo, a CI Solvent Green—9,10 Anthracenedione, 1,4 (dodecylphenyl), and their blends.
 10. An environment friendly writing instrument comprising: an ink pen comprising (I) a hollow body; (ii) an ink reservoir at the first end of the hollow body to hold ink; and (iii) a felt tip which extends from the reservoir to the second end of the hollow body; and a dye formulation comprising (I) a vegetable oil ester in an amount of between about 5 and 80 percent by weight of the dye formulation, (ii) a liquid solvent dye present in said dye formulation in an amount sufficient to impart a predetermined color to the dye formulation and (iii) sulfur in an amount of less than about 10 PPM; wherein said ink is formed from said dye formulation.
 11. An environment friendly automotive fluid comprising: transmission fluid; and a dye formulation in said automotive fluid comprising (I) a vegetable oil ester in an amount of between about 5 and 80 percent by weight of the dye formulation, (ii) a liquid solvent dye present in said dye formulation in an amount sufficient to impart a predetermined color to the dye formulation and (iii) sulfur in an amount of less than about 10 PPM; wherein the dye formulation is present in said automotive fluid in sufficient amounts to detect leaks in automobile transmissions; and wherein the dye formulation is present in said automotive fluid in sufficient amounts such that the levels of toxicity in said automotive fluid are substantially less than in an otherwise equivalent automotive fluid that include hydrocarbon-based dye formulation. 